IAN Holloway wants to turn Millwall into a "seamless" club.
His ambition is for the Lions' youth teams to play the same style of football as the senior side.
Rather than rely on a short-term loan signing to cover an injury, Holloway would prefer to promote from within – as long as the player making the step up is ready.
U21s boss Neil Harris is therfore a vital cog in the Millwall machine.
His job is to prepare the club's rising stars for the first-team environment, and get them following Holloway's philosophy from a young age.
It's been just over a year since Harris returned to The Den as a coach and the Lions legend believes huge strides are being made.
"That has progressed massively," he said. "It really helped that some of the players went away with the first team in pre-season.
"I've been able to watch quite a few of Ollie's training sessions and then deliver his message and way of doing things not just to the U21s but to the U18s as well.
"I've also been able to pick the brains of Ollie and Marc Bircham about organisation and structure.
"Sometimes it takes time for these things to feed down but it feels like we'e making huge progress and quite quickly.
"We feel that progress is paying off now with the likes of Jack Powell and Fred Onyedinma playing senior games this year.
"A couple of other guys have also been given the opportunity to come off the bench and play.
"The club has come a long way in a few years. We're now at a stage where the young lads, if they're good enough and perform to a high standard, they're given an opportunity."
The U21s have lost their last three games – to Nottingham Forest, QPR and Leeds – but Harris does not read too much into results.
He said: "It's important that we don't lose sight of the fact that these games are about development.
"Yes, it's lovely to win and that breeds confidence, but my sole aim is to prepare players to be ready to step into Ollie's first team.
"Those are our thoughts as a club with regards to the U21s. When they go onto the pitch it's not about winning the game, it's about whether they do things the Millwall way.
"Do they get their team structure right? Are they in the right positions? Do they cover each other? Are they playing in the same style as the first team?
"If our young players are doing those things, then Ollie will consider them good enough to make the step up to his squad. That's the main aim.
"We do like to get results but, win or lose, we need the lads to get into the right habits."